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排序方式: 共有265条查询结果,搜索用时 35 毫秒
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Abderrezak Abdi Omar Aaboubi Mohamed Trari 《Journal of Solid State Electrochemistry》2017,21(2):383-390
We report the synthesis and characterization of a new mesoporous cobalt oxide-infiltrated NaY zeolite prepared by ion-exchange route. The scanning electronic microscopy (SEM) image shows homogenous and uniform grains size distributions smaller than 1 μm, unlike to CoOx particles, elaborated under the same conditions. The energy dispersion spectroscopy (EDS) data confirm the presence of cobalt, oxygen, silicon, and aluminum. The X-ray diffraction indicates a partial crystallization of cobalt oxide and the formation of new phases. N2 adsorption-desorption measurement shows a high-specific surface area for the modified material (579 m2 g?1), with Barrett-Joyner-Halenda (BJH) pore diameters in the range (3–8 nm). The cyclic voltammetry indicates a typical faradic process, and the electrochemical impedance spectroscopy exhibits Warburg diffusion at low frequencies. The charge-discharge curve shows a clear improvement in the charge capacity of the modified material compared to CoOx, due to the increased specific surface area. The galvanostatic charge-discharge tests of the modified electrode exhibit a typical battery behavior preceded by a pseudo-capacitive phenomenon. 相似文献
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Maryam Ezoddin Khosrou Abdi Somaye Behnamipour Mahdiyeh H. S. Javadi 《Journal of separation science》2022,45(10):1757-1765
A free dispersive method, air-assisted in situ deep eutectic solvent decomposition followed by the solidification of floating organic droplets liquid-liquid microextraction was indicated in this study. This technique was utilized to simultaneously ascertain some azole antifungal drugs prior to high-performance liquid chromatography. In this research, a quasi-hydrophobic deep eutectic solvent was formed from tetrabutylammonium bromide and 1-dodecanol as an organic solvent at a 1:2 molar ratio. The synthesized deep decomposition in the sample solution caused in situ dispersion of extraction solvent and analytes. Air-assisted enhanced a dispersion condition in the sample solution. 1-Dodecanol as a green option was replaced with typical extraction solvents providing the advantages of a suitable freezing point near room temperature and low density. The effect of important analytical parameters on the extraction recovery of analytes was assessed. Under these optimal conditions, the limits of detection and the limits of quantitation determined were in the range of 0.5–2.8 and 1.5–9 μg/L, for water, urine and plasma samples, respectively. The intra-day and inter-day relative standard deviations (n = 5) were calculated to be 2.9–4.6 and 4.2–8.9%, respectively. The results represented the effectiveness of the developed method for the extraction and determination of analytes in biological samples. 相似文献
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S. H. R. Abdi R. I. Kureshy N. H. Khan V. J. Mayani H. C. Bajaj 《Catalysis Surveys from Asia》2009,13(2):104-131
This review is based on dimeric and polymeric chiral Schiff base metal complexes and chiral BINOL supported metal complexes
as potential recyclable catalysts for kinetic resolution of racemic and meso epoxide and asymmetric C–C bond formation reactions e.g., asymmetric addition of diethylzinc to aldehydes, enantioselective
addition of phenylacetylene to aldehydes, asymmetric nitro-Aldol reactions and asymmetric cyanation reaction. 相似文献
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Noor-ul H. Khan S. Saravanan Rukhsana I. Kureshy Sayed H.R. Abdi Arghya Sadhukhan Hari C. Bajaj 《Journal of organometallic chemistry》2010,695(8):1133-6983
Chiral dimeric vanadium (V) salen complex (10 mol%) derived from 5,5-Methylene di-[(S,S)-{N-(3-tert-butyl salicylidine)-N′-(3′,5′-di-tert-butyl salicylidene)]-1,2-cyclohexanediamine] with vanadyl suphate followed by auto oxidation was used as efficient catalyst for enantioselective Strecker reaction of N-benzylimines with TMSCN at −30 °C. Excellent yield (92%) of α-aminonitrile and high chiral induction was achieved (ee up to 94%) in case of 2-methoxy substituted N-benzylimines in 10 h. The catalytic system worked well up to four cycles with retention of enantioselectivity. 相似文献
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Dr. Alexander Britz Dr. Sergey I. Bokarev Dr. Tadesse A. Assefa Dr. Èva G. Bajnóczi Dr. Zoltán Németh Dr. György Vankó Dr. Nils Rockstroh Dr. Henrik Junge Prof. Dr. Dr. h.c. mult. Matthias Beller Dr. Gilles Doumy Dr. Anne Marie March Dr. Stephen H. Southworth Prof. Dr. Stefan Lochbrunner Prof. Dr. Oliver Kühn Prof. Dr. Christian Bressler Prof. Dr. Wojciech Gawelda 《Chemphyschem》2021,22(7):693-700
Time-resolved X-ray absorption spectroscopy has been utilized to monitor the bimolecular electron transfer in a photocatalytic water splitting system. This has been possible by uniting the local probe and element specific character of X-ray transitions with insights from high-level ab initio calculations. The specific target has been a heteroleptic [IrIII(ppy)2(bpy)]+ photosensitizer, in combination with triethylamine as a sacrificial reductant and as a water reduction catalyst. The relevant molecular transitions have been characterized via high-resolution Ir L-edge X-ray absorption spectroscopy on the picosecond time scale and restricted active space self-consistent field calculations. The presented methods and results will enhance our understanding of functionally relevant bimolecular electron transfer reactions and thus will pave the road to rational optimization of photocatalytic performance. 相似文献